The Correlation Between Iron Overload and Endocrine Function in Adult Transfusion-Dependent Beta-Thalassemia Patients with Growth Retardation

BACKGROUND: Iron overload is a major problem in patients with transfusion-dependent beta-thalassemia (TDT). Reports on the correlation between iron overload and endocrine function with growth retardation in such a population in Indonesia have not been established. Therefore, this study aims to obtain a profile of iron load and endocrine function of adult transfusion dependent beta-thalassemia patients and their correlation with growth retardation. METHODS: A cross-sectional study was performed, involving adult homozygous and HbE beta-thalassemia patients receiving blood transfusions at the Cipto Mangunkusumo Hospital, Jakarta. Iron overload was represented by serum ferritin (FS) and transferrin saturation (TS), while the endocrine function was examined by the Thyroid Stimulating Hormone-sensitive (TSHs), free T4 (fT4), and insulin-like growth factor-1 (IGF-1). The results were analyzed using bivariate analysis plus Pearson and Spearman correlation tests. RESULTS: In general, 58 subjects were selected from 224 adult transfusion dependent beta- thalassemia patients, consisting of 31 males (53.4%) and 27 females (46.6%). Furthermore, their median age was 21 (18–24) years, while the subclinical hypothyroid proportion was 32.7% and low IGF-1 levels were detected in 79.3% of the total population. There was a weak negative correlation between FS and fT4 (Spearman rho=−0.361; p=0.003), as well as IGF-1 (Spearman rho=−0.313; p=0.008), but FS and TSHs had no correlation (Spearman rho=0.074; p=0.29). Also, there was no correlation between ST with TSHs (Spearman rho=0.003; p=0.492), fT4 (Spearman rho=0.018; p=0.448), and IGF-1 (Spearman rho=−0.142; p=0.143). CONCLUSION: Based on serum ferritin, iron overload is discovered to have a negative correlation with free T4 and insulin-like growth factor-1.